Detergent motor fuel composition

ABSTRACT

Detergent motor fuel composition containing a carbamate represented by the formula: IN WHICH R is a hydrocarbyl radical having from about 12 to 20 carbon atoms and R&#39;&#39; is hydrogen or an alkyl radical having from one to two carbon atoms and x has a value from 2 to 4.

United States Patent Dorn et al. [4 1 Mar. 28, 1972 [54] DETERGENT MOTORFUEL Primary Examiner-Daniel E. Wyman I COMPOSITION AssistantExaminer-W. J. Shine Attorney-Thomas H. Whaley and Carl G. Ries [72]Inventors: Peter Dorn, Lagrangeville; Kenneth L. v

Dllle, Wappingers Falls, both of NY. [57] ABSTRACT [73] Ass g Tfllco Newlk,N.Y. Detergent'motor fuel compositlon containing a carbamate [22]Filed: MIL 26, 1970 represented by the formula:

211 App]. No.: 23,026 (H) RN-(CH2)x-"NHCR [52] U.S.Cl. ..44/66, 44/71[51] Int.Cl. ..Cl0ll/1,Cl0l 1/22 O=CO-)CHR) -OH [58] Field ofSelrch..44/63,66,7l;260/482C m Y' 1n WhlCh R 15 a hydrocarbyl radical havingfrom about I2 [56] References and to 20 carbon atoms and R is hydrogenor an alkyl radical having from 1 to 2 carbon atoms and x has a valuefrom 2 to UNITED STATES PATENTS 2,839,372 6/1958 Lindstrom et al ..44/663 Claims, No Drawings 3,468,639 9/1969 Lindstrom etal ..44/66 DETERGENTMOTOR FUEL COMPOSITION BACKGROUND OF THE INVENTION 1. Field of theInvention Modern internal combustion engine design is undergoingimportant changes to meet stricter standards concerning engine andexhaust gas emissions. A major change in engine design recently adoptedis the feeding of blow-by gases from the crankcase zone of the engineinto the intake air supply of the carburetor rather than venting thesegases to the atmosphere as in the past. The blow-by gases containsubstantial amounts of deposit-forming substances and are known to formdeposits in and around the throttle plate area of the carbure-. tor.These deposits restrict the flow of air through the carburetor at idleand at low speeds so that an overrich fuel mixture results. Thiscondition produces rough engine idling, stalling and also results inexcessive hydrocarbon exhaust emissions to the atmosphere.

2. Description of the Prior Art A gasoline which has carburetordetergency properties and in which one of the additive components is anN-alkyl-substituted alkylene diamine is disclosed in US. Pat. No.3,031,278. U.S. Pat. No. 2,991,162 discloses carburetor de-' tergentsadditives for gasoline obtained by reacting an N-alkyl propylene diaminewith ethylene carbonate or propylene carbonate to produce a twocomponentdetergent additive consisting of a carbamate and a urea compound.

SUMMARY OF THE INVENTION A class of relatively high molecular weightsubstituted carbamates are provided as carburetor detergents whenemployed in a liquid hydrocarbonaceous fuel for an internal combustionengine. These carbamates are characterized by being essentially neutralcompounds having no basic amino nitrogen yet, surprisingly, retainingtheir activity as carburetor detergents. This is an importantimprovement over some commercially available carburetor detergentshaving a basic amino nitrogen which reacts with acidic rust inhibitorsresulting in a loss of their detergency properties.

The fuel composition of the invention mitigates or overcomes the problemof deposits lay-down in the carburetor of an internal combustion engine.When a gasoline of the invention is employed in an engine in which thecarburetor has had a substantial build-up of deposits from prioroperations, a severe test of the detergency property of the fuel, thisgasoline is very effective .for removing substantial amounts of thepreformed deposits.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The substituted carbamateadditive employed in this invention may be represented by the followingformula:

in which R is a hydrocarbyl radical having from about 12 to about 20carbon atoms, R is hydrogen or an alkyl radical having from one to twocarbon atoms and x has a value from 2 to 4. In a preferred embodiment,the hydrocarbyl radicals indicated by R are aliphatic hydrocarbylradicals having from 16 to 18 carbon atoms and x has a value of 3.

The additive of the invention is prepared by reacting an amino-amide,with an alkylene carbonate under suitable conditions to produce thenoted compound. The amino-amides which can be employed are representedby the formula:

in which R is a hydrocarbyl radical having from about 12 to 20 carbonatoms and x has a value from 2 to 4. The preferred amino-amides arethose in which each R represents the same or different saturated orunsaturated aliphatic hydrocarbon radical having from 16 to 18 carbonatoms. Commercial amino-amides are available in which R represents amixture of aliphatic radicals derived from naturally occurringmaterials. Specific amino-amides which can be employed include: N-oleyltrimethylenediamine-oleamide (Duomeen O-Oleamide),N-cocotrimethylenediamine-oleamide (Duomeen C-Oleamide),N-stearyltrimethylenediamine-oleamide (Duomeen S-Oleamide), N-tallowtrimethylenediamine-oleamide (Duomeen T-Oleamide), N-C C see.alkyltrimethylenediamine oleamide, N-C C see. alkyltrimethylenediamineoleamide, N-C C sec. alkyltrimethylenediamine stearamide, N-C C sec.alkyltrimethylenediamine stearamide, N-dodecyltrimethylenediaminestearamide, N-dodecyltrimethylenediamine lauramide, andN-laurylethylenediamine dodecanamide. I

The alkylene carbonate component for preparing the additive of theinvention is represented by the formula:

in which R is hydrogen or an alkyl radical having from one to two carbonatoms. Particularly suitable compounds are ethylene carbonate andpropylene carbonate.

The amino-amide and the alkylene carbonate are reacted using at least 1mole of the alkylene carbonate per mole of the amino-amide in thereaction. The use of a substantial molar excess of the alkylenecarbonate, which assures substantial neutralization of the amino-amide,i.e. at least 75 percent neutralized or more preferably at least 90percent neutralized, is preferred and proportions of 1 to 2 moles ofalkylene carbonate per mole of the amino-amide are generally employed.The reaction is conducted by mixing the components and effecting thereaction at a temperature ranging broadly from about 0 to 165 C. Thepreferred reaction temperature range is from 50 to 150 C. This reactionmay be promoted by the use of a small amount of a catalyst, such asphosphoric acid.

Any gasoline suitable for a spark-ignited, internal combustion enginecan be used in the practice of this invention. In general, the base fuelwill consist of a mixture of hydrocarbons in the gasoline boiling range,that is boiling from about to about 450 F. The hydrocarbon components ofthe base fuel can consist of paraffinic, naphthenic, aromatic and/orolefinic hydrocarbons obtained by thermal or catalytic cracking orreforming of petroleum hydrocarbons. This base fuel will generally havea Research Octane Number from about to 102.

The carbamate of the invention can be advantageously employed in a motorfuel composition in a concentration ranging from about 0.0005 to 0.1weight percent. The preferred concentration of the additive is an amountfrom about 0.001 to 0.1 weight percent.

The following example illustrates the method of preparing the carbamateadditive.

EXAMPLE I One mole of N-oleyltrimethylenediamine-oleamide was heated toC., 0.8 weight percent of concentrated phosphoric acid added and 2 molesof propylene carbonate gradually added and reacted over several hours.The reaction mixture was continuously stirred overnight while being keptat about 150 C. Thereafter, the reaction mixture was cooled,

diluted with benzene and water-washed several times to remove excexcarbonate. The resultant solution was dried and stripped of solvent torecover the carbamate. The carbamate product had a TBN total basenumber, of about 10, a hydroxyl number of about 56 and was about 90percent neutralized.

The additives of the invention are tested for their effectiveness ascarburetor detergents for gasoline in the Chevrolet V-8 CarburetorDetergency Test. This test is run in a specially modified Chevrolet V-8engine mounted on a test stand and equipped with a four barrelcarburetor. The two secondary barrels of the carburetor are sealed andeach of the primary barrels modified so that an additive fuel can be runin one barrel while a base fuel is run in the other. The primarycarburetor barrels were previously modified so that they had removablealuminum inserts in the throttle plate area in order that depositsformed in this area could be conveniently weighed.

In a procedure designed to determine the eifectiveness of an additivefuel for removing preformed deposits in the carburetor, the engine isrun for a period of time usually 24 or 48 hours using the base fuel asthe feed to both barrels while the engine blow-by products arecirculated to the air inlet of the carburetor. The weight of thedeposits on both sleeves is determined and recorded. The engine is thencycled for 24 additional hours with the base fuel being fed to onebarrel, the additive fuel to the other barrel and no blow-by products tothe carburetor air inlet. The inserts are then removed from thecarburetor and weighed to determine the difference between theperformance of the additive and non-additive fuels in removing thepreformed deposits. After the aluminum inserts are cleaned, they arereplaced in the carburetor and the entire process repeated with thefuels feeds to the carburetor barrels reversed in order to minimizedifferences in fuel distribution and barrel construction. The depositweights in the two runs are averaged and the effectiveness of the basefuel and of the additive fuel for removing deposits expressed inpercent.

The base fuel employed in the following examples was a premium gradegasoline having a Research Octane Number of about 101 and containing 3cc. of tetraethyl lead per gallon. This gasoline consisted of about 25%aromatic hydrocarbons, 20% olefinic hydrocarbons and 55% paraffinichydrocarbons and boiled in the range from about 90 to 365 F. In certaincases indicated in the examples a minor amount of a conventional rustinhibitor and/or upper cylinder lubricating oil was used. These have nosignificant effect on the detergency test results.

EXAMPLE II Carburetor Detergency Test Additive Base Fuel Fuel A RunDetergency Additive propyl carbamate of N- The Base Fuel employed inthis Run contained 0.5 vol. percent of a mineral oil having an SUSViscosity at F. of about I00 and 72 PTS of a mineral oil solutioncontaining about 30 weight percent of a rust inhibitor from oxidizedmineral oil.

Indicates increase in deposits.

The Base Fuel contained 0.5 volume percent of a mineral oil blendconsisting of about 84% ofa mineral oil having an SUS Viscosity at I00F. of about 100. about 1% of a rust inhibitor and I5; of polypropeneof'about 850 average molecular weight.

The data show that the neutral carbamate of the invention, Run 1 retainsa high level of carburetor detergency when employed in gasoline ascompared to Runs 2 through 6 where this detergency property is lost. Run7 exemplifies a commercial gasoline detergent having a basic aminonitrogen function.

We claim:

1. A motor fuel composition comprising a mixture of hydrocarbons in agasoline boiling range and a minor detergent amount of a carbamaterepresented by the formula:

in which R is a hydrocarbyl radical having from about 12 to 20 carbonatoms and R is hydrogen or an alkyl radical having from one to twocarbon atoms and x has a value from 2 to 4.

2. A motor fuel composition according to claim 1 in which R is analiphatic radical having from 16 to 18 carbon atoms.

3. A motor fuel composition according to claim 1 in which x has a valueof 3.

2. A motor fuel composition according to claim 1 in which R is analiphatic radical having from 16 to 18 carbon atoms.
 3. A motor fuelcomposition according to claim 1 in which x has a value of 3.